IE34642B1 - Improvements in or relating to the fabrication of electrical circuit devices - Google Patents

Abstract

1315510 Welding by pressure WESTERN ELECTRIC CO Inc 6 Oct 1970 [8 Oct 1969] 47394/70 Heading B3R [Also in Division Hl] An assembly of a substrate carrying a plurality of conductive areas and a conductive member connected to one of the areas and overlying but insulated from another of the areas is made by forming the conductive member on a carrier, registering the carrier with the substrate and pressing the carrier against the substrate to bond ultrasonically or by thermo compression welding the conductive member to the conductive area the conductive member being deformed prior to or during the bonding. Cross-overs.-An aluminium plate 10 is coated with adhesive 12 and a gold layer which is photoetched to leave conductive members 16, 18. Members 16, 18 are punched to recess them into the aluminium which is then registered with the conductive tracks 22 on a substrate 20, Fig. 1D. The members 16, 18 are bonded to the tracks 22 by heat and pressure applied to the substrate 20 and/or plate 10. In a modification, Figs. 2A-2E (not shown), the aluminium plate is replaced by a steel plate apertured or recessed to receive the conductive member and also an integrated circuit. The adhesive layer is replaced by a polyimide film. The film may be copper coated, in which case the conductive member may be produced using a gold etch resist position using a negatively exposed photoresist. The conductive member may comprise several layers of conductor and polyimide to provide power planes, ground planes, &c. In another embodiment, Figs. 4A-4C (not shown) a solid material is applied over the conductive track to be crossed before the crossover is bonded in place. The solid material may then be etched away or if a dielectric left in place. Capacitors.-A thin film capacitor, Fig. 5C produced by forming a bottom electrode 66 and a conductive portion 64 on a substrate 62. The top electrode 72 is formed on a carrier, which after the dielectric 70 has been applied to top or bottom electrode is registered with the substrate and the top electrode is bonded to the conductive portion 64. [GB1315510A]